So let's just say it off the top: using these apps is
cheating and might get you banned. The vast majority
of these apps are explicitly against Niantic's rules, and if
you use them, there's a very good chance they'll ban your
Pokémon Go account permanently.

Here's the pertinent part of Pokémon Go's
policy, buried about halfway through. You agreed to this
policy when you signed up for the game, even if you didn't read
it. It says you cannot:

"...attempt to access or search the Services or Content,
or download Content from the Services through the use of any
technology or means other than those provided by Niantic
or other generally available third-party web browsers (including,
without limitation, automation software, bots, spiders, crawlers,
data-mining tools, or hacks, tools, agents, engines, or devices
of any kind)...."

The good news is, some mapping tools like
the mega-popular Pokevision, which works with a web browser,
doesn't require you to use any login. So they won't know it's
you.

Pokevision, a popular site
that lets you see what Pokémon are in a given
area.Screenshot/PokeVision

But another Niantic's terms of service also prohibits
"extract, scrape, index, copy, or mirror," meaning they'd
be within their rights to shut down Pokevision, too. That goes for
iPhone apps like the similar
PokeWhere, as well.

The absolute best tools, like
PokeDetector and
PokeNotify, both for Android, can actually send you push
notifications or texts when rare Pokémon appear in
your vicinity.

Apps
like PokeDetector charge for premium services, another no-no
according to the terms of service.Cameron Merriman/Business Insider

But they require you to enter a game account login, since that's
how it accesses the Pokémon location data. Plus, some of
them charge for premium services, like this screenshot of
PokeDetector offering you a Premium upgrade so you can choose
which Pokémon you get notified about.

That's another no-no according to Niantic. Be
warned.

And while savvy players are creating throwaway, one-
time use accounts just for the app, lots of players are using
their main Pokémon Go account. And whether you're using a Google
account or a Pokémon Trainer's Club account to log in,
Niantic can definitely see what you're doing.

So, yes, it's frustrating that Pokémon Go is currently
broken to the point where it's way harder than it needs to be to
find hidden Pokémon. Just know that you're taking your
account and your future Pokémon journeys into your own hands
if you use them.

And while the Pokémon Go servers are all funky, it's still
pretty legit to use "Ingress," Niantic's previous game, as a tool
to help hunt rare Pokémon.
Here's how.

Niantic did not respond to a request for comment, but we'll
update if we hear back.